`Older` Button is Clickable When No More Search Results Exist

[prikhi]

1. Type tic tac into search box - or anything with only one page of search results.
2. Scroll down past search results.
3. Click the Older button.

After clicking the button you are brought to a blank page.

The Older button should be grayed out & clicking it should do nothing since there are no more search results to display.